\u00a9 2023 wikiHow, Inc. All rights reserved. Catch the entire MCAT Math series on my website here: http://leah4sci.com/mcat-math-without-a-calculator/Need more help? We can convert pKa to Ka as. How to Convert Ka to pKa, Formula, Equation & Examples of. Best of all, Pka to ka online calculator is free to use, so there's no reason not to give it a try! wikiHow, Inc. is the copyright holder of this image under U.S. and international copyright laws. pKa calculator. If you're looking for a quick delivery, look no further than our company. pK to K Conversion Since pK a is the negative logarithm of K a, the value of K a can be calculated by simply reversing the above equation. Deriving Ka from pH wikiHow, Inc. is the copyright holder of this image under U.S. and international copyright laws. To create a more manageable number, chemists define the pKa value as the negative logarithm of the Ka value: pKa = -log Ka. pKa = -log Ka. wikiHow, Inc. is the copyright holder of this image under U.S. and international copyright laws. You solve this by raising both sides of the original relationship to powers of 10 to get: When pKa is a whole number, such as -7, this operation is easy to perform, but when it contains a fraction, such as 7.5, you may have to look up the value in a table. HA (aq) + H 2 O (l) H 3 O + (aq) + A - ( aq) Ka = [A - ] [H 3 O +] / [HA] We can calculate the Keq (equilibrium constant) or Ka of a reversible acid-base reaction. Math which you MUST be able to complete quickly and confidently without a . The pKa to pH converter calculator is an online tool that can find the pH of a liquid solution using the pKa value and concentration. without app I would have to work 5-6 hours tryna find the answer and show work but when I use this I finish my homework in 30 minutes or so, the camera caption has improved overtime . This is so much faster than looking all over the internet to find an answer to compare to, it may not work on word problems but this does work for any type of number problem. Substitute your known pKa value into the equation from the previous step. If you're struggling with a math problem, scanning it for key information can help you solve it more quickly. Use the relationships pK = log K and K = 10pK (Equation 16.5.11 and Equation 16.5.13) to convert between K_a and pK_a or K_b and pK_b. You can get math help online by visiting websites like Khan Academy or Mathway. 1.Use the equation Ka=10-pKa{\displaystyle Ka=10^{-pKa}} for this conversion. Thought this trick was commonly known. Example: wikiHow, Inc. is the copyright holder of this image under U.S. and international copyright laws. This formula is based on the definition of pKa which is the negative logarithm of the acid dissociation constant. etc. . The mathematical operation you perform is Ka = antilog (-pKa). Equations for converting between Ka and Kb, and converting between pKa and pKb. Include your email address to get a message when this question is answered. To convert Ka into pKa, get out your calculator and find -log . To create a more manageable number, chemists define the pKa value as the negative logarithm of the Ka value: pKa = -log Ka. This image is not<\/b> licensed under the Creative Commons license applied to text content and some other images posted to the wikiHow website. It can be used to calculate the concentration of hydrogen ions [H+] or hydronium ions [H3O+] in an aqueous solution. His writing covers science, math and home improvement and design, as well as religion and the oriental healing arts. You do need to pay to get worked out solutions but in a pinch it can at least speed up getting your desired answers, sometimes you have to pay to see the steps and explanation, but for the most part it's free. Estimating Ka from pKa (lets say it equals 10.63) is a bit trickier and less accurate: Round to a single digit after the decimal as needed: 10.63 10.7. Best calculator, but other than that. As: pH = pKa + log([A]/[HA]) So, The calculator uses this formula to . Solution. Thus K a is the antilogarithm of the negative of pK a. K a = antilog (-pK a) The logarithm of a number x is the exponent that the number 10 should be raised, to obtain x. Therefore to convert pKa to Ka just find 10^ -pKa in the scientific calculator, you will get it. Harold Hammer. The correct formula is Ka=10-pKa K a = 10 - p K a . pH of acid by pKa. 00:0000:00 An unknown error has occurred Brought to you by eHow 1.Use the equation Ka=10-pKa{\displaystyle Ka=10^{-pKa}} for this conversion. calculator, How to find the lateral area of a triangular prism formula, How to make frequency table in statcrunch, How to prove a piecewise function is differentiable, Initial value differential equation solver, Properties of negative and zero exponents homework 3. Alternatively, it can be used to find the pOH value of a base by inputting its pKb value in the "pKa=" input field. This image is not<\/b> licensed under the Creative Commons license applied to text content and some other images posted to the wikiHow website. When citing the strength of an acid, chemists often use the dissociation constant, Ka, but this number can vary by several orders of magnitude from one acid to another. pKa = -log10Ka . The dissociation constant for a strong acid can be as high as 10^7 while for a weak acid it can be as low as 10^-12. This is especially useful in Chemistry questions asking you to solve H+, OH-, or general ion concentrations, not to mention ka and kb values This video teaches you how to solve the potentially impossible MCAT logarithm questions without a calculator by showing you what to look for and numbers to recognize for simple and fast conversions. For maintaining the precise and accurate pH of the buffer solution follow the steps Input: Select the buffer type Enter the pKa Enter Acid or base concentration Enter Relative salt concentration If you already know the pKa value for an acid and you need the Ka value, you find it by taking the antilog.